20388420642 has 16 divisors (see below), whose sum is σ = 41235009120. Its totient is φ = 6719778912.

The previous prime is 20388420599. The next prime is 20388420643. The reversal of 20388420642 is 24602488302.

It is a self number, because there is not a number n which added to its sum of digits gives 20388420642.

It is not an unprimeable number, because it can be changed into a prime (20388420643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19089748 + ... + 19090815.

It is an arithmetic number, because the mean of its divisors is an integer number (2577188070).

Almost surely, 2^20388420642 is an apocalyptic number.

20388420642 is an abundant number, since it is smaller than the sum of its proper divisors (20846588478).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20388420642 is a wasteful number, since it uses less digits than its factorization.

20388420642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38180657.

The product of its (nonzero) digits is 147456, while the sum is 39.

The spelling of 20388420642 in words is "twenty billion, three hundred eighty-eight million, four hundred twenty thousand, six hundred forty-two".